This invention relates to an adhesion preventive. More particularly, it relates to a material useful in surgical operations for preventing adhesion of vital tissues such as skin, blood vessels or organs.
Vital tissues such as blood vessels or organs including kidney, liver and intestines are coated with mucous membranes or serous membranes so that they can function independent of each other. For example, there are body wall pleura and organ pleura in the thoracic cavity and parietal peritoneum and mesentery in the abdominal cavity, each protecting the corresponding organs. Surgical operations or inflammation in those portions of the body coated with serous membranes could result in adhesion regardless of the size of the affected part. Such adhesion between vital tissues may be observed not only in particular portions of the body but in all vital tissues. Adhesion between vital tissues has heretofore presented a serious problem in the surgical field.
In the field of orthopedics, acute or chronic arthritis such as suppurative, gonorrheal, tuberculous or rhemumatoid arthritis or traumatic injuries at a joint such as fracture or sprain would result in ankylotic diseases wherein the surface of the bones constituting the joint adhere to each other and thereby restrict the mobility of the joint. Congenital radioulnar synostosis wherein a spoke bone and an ulna adhere together at the proximity is difficult to remedy by a surgical operation, since the separated bones would frequently readhere.
When neural spine and spinal cord are removed dorsally by a surgical operation in a vertebral canal cavity in treating myeloma, hernia of intervertebral or adhesive spinal meningitis, it is necessary to prevent adhesion to the body wall. Further, suturing of ruptured tendons and tendon transfer would sometimes fail because of the postoperative adhesion of the tendon to the scar in the skin. Furthermore, in the case of rupture of a flexor tendon between a metacarpophalangeal joint and a proximophalangeal joint, the function of the finger would not recover by the intermittent suture of musculus flexor digitorum superficialis and musculus flexor digitorum profundus since these tendons injured simultaneously would adhere to each other. Therefore, it is also necessary to prevent adhesion between the two tendons in this case.
In the field of thoracosurgery, bronchi dilated by primary diseases such as pulmonary or suppurative diseases would allow the extension of inflammation over the surrounding pulmonary parenchyma and the formation of suppurative focus to thereby result in adhesion to pleura. In addition, lung cancer would result in adhesion of a focus to the body wall.
In the field of abdosurgery, external damages such as disjunction or rupture by a severe impact or morbid damages such as inflammation or tumor in organs in an abdominal cavity including liver, kidney, pancreas, spleen and intestine would result in adhesion of organs to each other or of an organ to the abdominal wall. Rupture of the diaphragm or peritoneum caused by a severe external closed damage would result in adhesion of an organ to the abdominal wall. Further, ileus of the small or, large intestine, which has the same meaning as intestinal obstruction and generally refers to an acute obstruction, would be mainly caused by adhesive ileus wherein the intestinal cavity is closed by a crooked or flexed intestinal tract resulting from adhesion in the abdominal cavity most of which would be formed postoperatively. Therefore, it is necessary to prevent adhesion in the abdominal cavity after the operation to prevent said adhesive ileus. Abdominal abscess could sometimes result in adhesion of peritoneum, diaphragm or pleura to each other. In addition, adhesion between adjacent organs or of an organ to the abdominal wall should be prevented in the case of various diseases or tumors which cannot be removed completely in internal organs.
In the fields of obsterics and gynecology, endometritis, excessive artificial abortions or intrauterine curettage would sometimes result in partial or whole adhesion of placenta to uterine wall, which makes separation of the placenta at delivery difficult. Furthermore the primary focus of breast cancer would multiply remarkably to thereby adhere to skin or a tendon.
In the field of brain surgery, adhesive arachnitis would be induced by chronic or suppurative intracranial inflammation resulting from an unknown primary cause, syphilis, tuberculosis, or the like, a sequela of an external damage in head, intrahecal injection of medicine in therapy, or myelography.
In addition, adhesion resulting from facial palsy which is caused by a malignant tumor in the salivary gland would sometimes restrict mobility. A cervical lymph node timefied by transfer of cancer would consolidate and adhere to the surrounding tissues to thereby restrict mobility.
As described above, adhesion of vital tissues, large or small, may be observed in most of the surgical fields. Adhesion could occur for various reasons including mechanical and chemical stimulations of vital tissues accompanying surgical operations, postoperative bacterial infection, inflammation or complications. Consequently, it is necessary to prevent postoperative adhesion between vital tissues.
Conventional adhesion preventives such as liquid paraffin, camphor oil, chondroitin sulfuric acid and urea exhibit an insufficient effect since they function only temporarily. On the other hand, polymer membranes such as gutta percha or poly(tetrafluoroethylene), which have been used for preventing postoperative adhesion at portions of the body where there is a fear of adhesion setting in, would remain in the body as foreign bodies. Therefore, it is desirable to take out the used membrane by reoperation.